And to the fast-moving developments overseas tonight. For a key american ally. More clashes and chaos in turkey, where police fired tear gas and water cannons at protesters. At the same time, the prime minister was holding his own rally. Tonight, defending his crackdown. Abc's alex marquardt is in istanbul. Alex? Reporter: Good evening, david. It's been a day of brutal crackdowns here in istanbul. The anti-government protesters have been violently uprooted from the park they've been occupying. The police tonight won't let us get anywhere near it. As the government launches an all-out effort to quash this two-week protest. It's tiolence turkey has seen in decades. Today, running battles between police and the anti-government protesters. Suffocating amid vast clouds of tear gas. Protesters refused to leave this park for over two weeks, despite repeated angry warnings from turkey's prime minister that he would clear the park. Last night, he made good on that promise. The protesters blame the prime minister for the police's brutality, for acting like a dictator and a long list of undemocratic grievances. The prime minister is one of america's best friends. A key regional ally for the war in syria and against iran's nuclear program. Tonight, at a massive rally, a defiant prime minister made no apologies, telling supporters and the world that those in the square are just a minority and do not represent turkey. It's hard to say where this protest mont goes from here. It's clear that the security services will not tolerate the kind of unrest we've seen. But these violent crackdowns have only energized the protesters.

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